Winter Annual Weed Management
Posted: October 1, 2012
Look out for those seedlings that have already started germinating, as in this photo of winter annuals that have germinated in a disease-damaged lawn.
Remember way back in March and April when lawns and landscapes were inundated with winter annual weeds? This is your reminder to manage for them this fall.
Winter annual weeds (like hairy bittercress, purple deadnettle, henbit, common chickweed, annual bluegrass, and many others) can germinate from fall to early spring. They flower and set seeds in early to mid spring, then die when summer heat takes over. All those seeds are in the soil, ready to sprout now that cooler temperatures are here. Many winter annuals tolerate and even grow during the cold weather of winter. Some have started germinating already in a lawn or landscape near you.
When developing your plan of attack, carefully inspect turf or landscape beds to look for seedling emergence. If the winter annuals have already germinated, it will be necessary to use a post-emergence herbicide treatment or physically remove them. Then, take steps to prevent more of their seeds from germinating.
Some things you can do this fall to help prevent them include:
- Refreshing mulch to cover bare ground areas
- Repairing thin or bare areas in turf by over-seeding (best done now through mid-October)
- Applying a pre-emergent herbicide to landscape beds or turf
Your efforts this fall should result in a more weed-free spring.
- Educator, Regional Turf Specialist